"May I ask you to let me know sometime what you think of
Mr. Popper. He gave a lecture here, on the task of social philosophy,
that was beneath contempt: it was the most washed-out, lifeless
positivism trying to whistle in the dark, linked to a complete inability
to think “rationally,” although it passed itself off as
“rationalism”–it was very bad. I cannot imagine that such a man ever
wrote something that was worthwhile reading, and yet it appears to be a
professional duty to become familiar with his productions. Could you say
something to me about that–if you wish, I will keep it to myself.
Warmest greetings,
Leo Strauss

April 18, 1950
Dear Mr. Strauss,

The opportunity to speak a few deeply felt words about Karl Popper to
a kindred soul is too golden to endure a long delay. This Popper has
been for years, not exactly a stone against which one stumbles, but a
troublesome pebble that I must continually nudge from the path, in that
he is constantly pushed upon me by people who insist that his work on
the “open society and its enemies” is one of the social science
masterpieces of our times. This insistence persuaded me to read the work
even though I would otherwise not have touched it. You are quite right
to say that it is a vocational duty to make ourselves familiar with the
ideas of such a work when they lie in our field; I would hold out
against this duty the other vocational duty, not to write and to publish
such a work. In that Popper violated this elementary vocational duty
and stole several hours of my lifetime, which I devoted in fulfilling my
vocational duty, I feel completely justified in saying without
reservation that this book is impudent, dilettantish crap. Every single
sentence is a scandal, but it is still possible to lift out a few main
annoyances.
1. The expression “closed [society]” and “open society” are taken from Bergson’s Deux Sources.
Without explaining the difficulties that induced Bergson to create
these concepts, Popper takes the terms because they sound good to him;
[he] comments in passing that in Bergson they had a “religious” meaning,
but that he will use the concept of the open society closer to Graham
Wallas’s “great society” or to that of Walter Lippmann. Perhaps I am
oversensitive about such things, but I do not believe that respectable
philosophers such as Bergson develop their concepts for the sole purpose
that the coffeehouse scum might have something to botch. There also
arises the relevant problem: if Bergson’s theory of open society is
philosophically and historically tenable (which I in fact believe), then
Popper’s idea of the open society is ideological rubbish. For this
reason alone, he should have discussed the problem with all possible
care.

2. The impertinent disregard for the achievements in his particular
problem area, which makes itself evident with respect to Bergson, runs
through the whole work. When one reads the deliberations on Plato or on
Hegel, one has the impression that Popper is quite unfamiliar with the
literature on the subject–even though he occasionally cites an author.
In some cases, as for example Hegel, I would believe that he has never
seen a work like Rosenzweig’s Hegel and the State. In other cases, where he cites works without appearing to have perceived their contents, another factor is added:

3. Popper is philosophically so uncultured, so fully a primitive
ideological brawler, that he is not able even approximately to reproduce
correctly the contents of one page of Plato. Reading is of no use to
him; he is too lacking in knowledge to understand what the author says.
Through this emerge terrible things, as when he translates Hegel’s
“Germanic world” as “German world” and draws conclusions from this
mistranslation regarding Hegel’s German nationalist propaganda.

4. Popper engages in no textual analysis from which can be seen the
author’s intention; instead he carries the modern ideological clichés
directly to the text, assuming that the text will deliver results in the
sense of the clichés. It will be a special pleasure for you to hear
that, for example, Plato experienced an evolution–from an early
“humanitarian” period still recognizable in the Gorgias, to something else (I can’t recall any more if “reactionary” or “authoritarian”) in the Republic.

Briefly and in sum: Popper’s book is a scandal without extenuating
circumstances; in its intellectual attitude it is the typical product of
a failed intellectual; spiritually one would have to use expressions
like rascally, impertinent, loutish; in terms of technical competence,
as a piece in the history of thought, it is dilettantish, and as a
result is worthless.
It would not be suitable to show this letter to the unqualified.
Where it concerns its factual contents, I would see it as a violation of
the vocational duty you identified, to support this scandal through
silence.
Eric Voegelin

My dear Mr. Voegelin,
I have never thanked you for your interesting letter dated 18.4. In
confidence I would like to tell you that I showed your letter to my
friend Kurt Riezler [احتمالا این فرد], who was thereby encouraged to throw his not
inconsiderable influence into the balance against Popper’s probable
appointment here. You thereby helped to prevent a scandal."